Organic Light-Emitting Diode (OLED) devices are featured by self-light emitting, high brightness, high contrast, low operating voltage, flexible display and so on, and are regarded as the most prospective display devices. However, compositions in the air such as moisture and/or oxygen and so on greatly affect the service life of OLED devices. Thus, OLED devices usually need to be encapsulated to isolate the OLED devices from the air.
In the related art, an OLED device includes a basal substrate and an anode layer, a pixel definition structure (or referred to as a pixel definition layer (PDL)), an organic light-emitting layer and a cathode layer arranged sequentially on the basal substrate. The pixel definition structure includes a plurality of barriers with the same height. The plurality of barriers may define a plurality of pixel regions. The organic light-emitting layer includes a plurality of organic light-emitting units. Each organic light-emitting unit is disposed in one pixel region. When an OLED device is encapsulated, an encapsulation structure may be formed at an outer side of the OLED device. The encapsulation structure includes an organic layer and an inorganic layer alternately laminated on and covering the OLED device. There may be a plurality of organic layers and inorganic layers. The inorganic layer may be formed through an atomic layer deposition (ALD) process. When the inorganic layer is formed through the ALD process, the OLED device may be deposited in a deposition cavity, then a mask plate may be provided in the deposition cavity such that the mask plate is disposed on the OLED device and an opening area of the mask plate corresponds to the OLED device, and a gas phase precursor may be input into the deposition cavity through a gas inlet at one side of the deposition cavity. The gas phase precursor spreads in the deposition cavity and is deposited and attached to the OLED device through the opening area of the mask plate to form an inorganic layer.
During the implementation of the present disclosure, the inventors have found at least the following problems in the related art:
Since the barriers of the pixel definition structure have the same height, when an inorganic layer is formed through the ALD process, the inorganic layer on the OLED device which first contacts the gas phase precursor is relatively thick, causing poor thickness uniformity of the film layers of the OLED device after encapsulation and a poor encapsulation effect.